Battery with fuel cells of solid electrolyte

ABSTRACT

A battery made up of fuel cells each having a solid electrolyte for direct conversion of chemical energy liberated in the oxidation of a combustible gas into electrical energy. The fuel cells are arranged in series each forming a subchamber and being combined into a chamber for the combustible gas. Each fuel cell has one electrode on an inner wall of the subchamber and its other electrode on an outer wall of the cell. The subchamber is formed by each of two successive cells with a temperatureresistant packing between cells so as to exert a sealing effect obtained by a force compressing the cells and packings. Each fuel cell is in the form of a portion of a cylinder made in one or two pieces having a cylindrical periphery and faces perpendicular to its axis, at least one face being recessed and the subchamber formed by putting two successive cells together.

References Cited Feeley ry made up of fuel cells each having a rectconversion of chemical energy UNITED STATES PATENTS 1/1970Tomter.........................

gs. Each fu 3,508,970 4/1970 Grubb et Primary Examiner-Winston A.Douglas Assistant Examiner-H. A. Attorney-Jacobs & Jacobs ABSTRACT: Abatte solid electrolyte for di liberated in th id energy. Thefuel cellsar subchamber and bein bustible gas. Each fu of the subchamber and thecell. The subchamber is cells with a temperature to exert a sealin cellsand packin a cylinder made in one o periphery and faces perpen beingrecessed and the subchamber successive cells together.

Hens Hermann Eysel am Kirchwnld, Germany 860,900 Sept. 25, 1969 Oct. 26,1971 Brov'vn, Boverl 8t Cie Alrtiengesellschlft Kllktndter Str. 1,Germany Nov. 20, 1968 Germany P 18 09 878.7

L CELLS 0F SOLID ELECTROLYTE 5 Chims, 9 Drawing Figs. [52]U.S.Cl..............

Field of Search...

United States Patent" [72] Inventor 2'1 Appl.No.

22] Filed [45] Patented [73] Assignee [32] Priority [$4] BATTERY WITHPUB PATENTEDam 2 6 \sn SHEET 10F 2 Fig. 7b

PATENTEDUCT 26 I9" SHEET 2 BF 2 ef ii Inventor Maw/7 5x: mam

BATTERY WITH FUEL CELLS OF SOLID ELECTROLYTE This invention relates to abattery with a .pluralityof fuel a high oxygen ion conductivity andreferred to as solid elec-.

trolyte It is provided on either side with electrodes and currentoutlets. One electrode is supplied with the fuel, for example hydrogen,and the other electrode with oxygen, for example as a constituent of theair. ,The oxygen partialpressure determined by the position of thechemical equilibrium is very different on the two sides of the cell.This leads to the establishment of a potential difference between thetwoelectrodes, so that electrical energy can be withdrawn from the cellbyway of a consuming circuit. The oxygen migrating through the solidelectrolyte during the passage of current owing to the ionic outputmechanism, reacts with the'fuel by an electrochemical anode reaction. Inthese processes, essentially the kinetics ofthe two electrodes and theelectrodes and the electrolyte resistance determine the electrochemicalefficiency, while the position of the equilibrium of theoxidation-reduction reaction determines the utilization capacity of thefuel.

It is known (e.g., BBC-Mitteilungen l966,p. 29 thata plurality of suchcells may be combined to form a battery. One of the main problems in themanufacture of such batteries is the sealing technology which isdifficult because of the highoperating temperature. In particular, thefusing of thetubular gas chambers to disc-shaped electrolytes of smallthickness and the simultaneously necessary gastight passage of thecurrent outlets involve production difficulties. Finally, the minimumdimensions of tubular gas chambers required for acceptable M of suchconnection techniques lead to low output density and a high'weight-powerratio.

The object of the present invention is to avoid the disadvantages ofknown fuel cells, and in particular to provide a fuel cell in which thegas chambers arekept very small, the fusing-in of current outlets iseliminated, and special conformation of the electrolyte disc saves, oneseal per disc.

To solve this problem, the invention proceeds from a bat-.

tery with a plurality of fuel-cellsconsisting of; av solidelectrolytefor direct conversion of the chemicaLenergy liberated in the oxidationof a fuel gas into electrical energy, wherein the fuelcells, arranged in,seriesand forming a subchamberin,

each instance, are combined intoa connected chamber containing the fuelgas, and'wherein a fuel;cell bears one electrode on an inner wall of thesubchamber and the other electrode on an outer wall-of the cell. Theinventioncomprises a subchamber formed by each two successive cells witha temperature-resistant packing arranged between the cells, the sealingeffect of whichis produced by a force compressingthe cells and thepackings.

In the accompanying drawings, embodiments of. theinvention arerepresented by way of example:

FIGS. la and 1b show a battery module consisting of two separatedisc-shaped members of solid electrolyte;

FIGS. 2a to 2f show a battery module consisting of a onepiece solidelectrolyte member; and,

FIG. 3 shows in fragmentary longitudinal section a battery made up ofbattery modules according to FIGS. 2a to 2b In FIG. la, the first discof the module has a circular cross section. On one side, it has anannular elevation 1 at the edge. Inside this edge, the fuel electrode(Anode I) 2 is arranged. Further, the element has a hole 3 extendingtherethrough, and on the under side, the Cathode I" (not visible in thedrawing) cut out only in the region of thehole. From Anode I, aconducting strip 4 passes around the edge of the disc to the under sideof the disc in the region of the hole, while a conducting strip 5 passesfrom Cathode I to the annular elevation. FIG. lb shows the other disc ofthe module. It has three or more arcuate elevations 6. 7 on one side. Ofthese, the elevation 7 is enlarged'to accommodate a hole 8. This side ofthe element is covered with the oxygen electrode 9 (Cathode II) whichalso covers the elevations 6 and is conductively connected by themto-Cathode I upon assembly. 0n the under side of this element is AnodeII, cutting out an annular rim. From Anode II, a conducting strip 10leads to the top of elevation 7. By way of one of the elevations 6, aconductive strip 11 leads to the electrodeless edge of the under side.Conductors 4 and I0 connect Anodes I and" of the module in parallel.Holes 3 and 8 connect the gas chambers in contact with the anodes. Theelementsof FIGS. la and lb, aligned as shown, form a battery module. Theseveral modules are stacked with interpostion of an asbestos felt gasketmetallized in certain areas only. The battery is thereby circuited inparallel when the conductors 4 and 10 and conductors 5 and 11 of eachtwo modules are conductivelyconnected, whereas for circuiting in series,conductors 5 and 10 of two modules are connected and conductors 4 and 11insulated from each other.

The. fixedly connected module of FIGS. 2a to 2}" may be understood byreference to a numbering analogous to that of FIGS. la and 1b. FIG. 2ashows the under side of the module with Anode II 12 and the twoconductive strips 10 and 11. FIG. 2bis a section of the module in aplane between the two discs with the Cathode I 13 in view, which in thisform of the invention covers the insides of all elevations 6 and 7, hereforming bridges between the two discs and thus is conductively connectedtothe Cathode II 9..The enlarged bridge 7 contains the hole 8 passingthrough both elements. Through this hole, again, the fuel gas chambersof the battery communicate. FIG. 20 shows a section AB parallel to thecenterline of the battery through both discs of a module. A projectiononto the CD plane illustrates the represented features in FIG. 2d. FIG.2e again represents the top face of the module with the Anode I 2 andthe electrode-free elevated rim 1. FIG. 2}, finally represents the samesection as FIG. 2b, viewed in the opposite direction. It shows theCathode II 9.

The solidelectrolyte members of FIG. I or of FIG. 2, as many as desiredplaced upon one another, are pressed together in gastight manner at theinterposed gaskets 17 by means of two flanges l5, 16 into one or morestacks within a common tubular sleeve. FIG. 3 illustrates this for abattery with solid electrolyte members according to FIG. 2c. The pipeconnections 18, 19 serve to carry combustible gas, and pipeconnections20, 21 oxygen or air. FIG. 3 further shows the modulescircuited in series; for circuiting in parallel, analogously to theembodiment of the invention first described, the modules must be sosuperimposed that the metallized areas of the gaskets conductivelyconnnect like electrodes of different modules in each instance. In bothcases, the gaskets at the flanges are each provided with one conductivearea only, so that one flange becomes the positive pole and the otherthe negative pole of the battery.

What is claimed is:

l. A battery for the direct conversion of chemical energy liberated inthe oxidation of a combustible gas into electrical energy comprising aplurality of fuel modules arranged in series between compressing means,each fuel module consisting of two disc-shaped elements each of whichhas a solid electrolyte, a first anodic electrode on one surface and asecond cathodic electrode on its other surface, one of the disc-shapedelements of each fuelmodule having a plurality of arcuate elevationswhich form a subchamber space in the module whereby the two elements ofeach module are arranged so that only one type of electrode forms partof the subchamber, the battery further comprising a tubular sleevespaced from the modules to produce a first gas chamber in communicationwith the subchamber, a plurality of temperature-resistant sealinggaskets arranged between the fuel modules and spacing second gaschambers between the modules, the second gas chambers beingincommunication by means of holes extending through the modules, eachsealing gasket comprising at least one metallized area which is incontact with strip conductors connected to the electrodes of adjacentfuel modules.

4. A battery according to claim 1, wherein the compressing means includetwo flanges which are connected by bolts.

5. A battery according to claim 4, wherein the flanges are in electricalcontact with adjacent sealing gaskets, one flange becoming the positivepole of the battery and the other flange becoming the negative pole.

2. A battery according to claim 1, wherein the strip conductors of eachmodule are arranged on the cylindrical periphery thereof, a first stripconductor connecting the first electrodes of each module and a secondstrip conductor connecting the second electrodes.
 3. A battery accordingto claim 1, wherein the solid electrolyte consists of an oxide ceramicmass with high oxygen ion conductivity.
 4. A battery according to claim1, wherein the compressing means include two flanges which are connectedby bolts.
 5. A battery according to claim 4, wherein the flanges are inelectrical contact with adjacent sealing gaskets, one flange becomingthe positive pole of the battery and the other flange becoming thenegative pole.